Soyuz launch will be delayed

Docking unit

28 September 2004

Russia will launch a three-man crew to the International Space Station on 11 October 2004, two days later than initially scheduled due to problems with the docking system, Vaicheslav Davidenko, FSA spokesman reported on 22 September 2004. A few days later the same source reported more troubles encountered during the fuelling operations of the Soyuz-TMA at Baikonur, due to which the launch will be further delayed.

Russia's space agency announced the delay has not yet given a new launch date.

Earlier reports from RSC Energia said that the decision had been taken to replace the whole docking unit between the two separating compartments of the Soyuz-TMA spaceship.

Initial reports from Russia's Federal Space Agency in Moscow referred to a potential Soyuz launch delay due to technical problems with the docking system.

Vyacheslav Davidenko reported on 15 September 2004 that specialists were working to repair the manned Soyuz spaceship as quickly as they could. “A special commission was created in Baikonur, which will check the functioning of all the systems of the spaceship and will remove the defects as soon as possible,” he said. “The safety of the crew is the most important thing for us. Nevertheless, we set ourselves the task of preparing the spaceship for launching before 9 October, which is the planned date.” At the same time, he does not rule out a possibility of postponing the launching of the Soyuz TMA-5 with three cosmonauts on board for five to ten days. In this case the return to the Earth of Gennady Padalka and Michael Fink, who have been working at the International Space Station (ISS) since last April, will also be postponed.

Soyuz spaceship

“The reason for a postponement of the Soyuz launch was the sudden plop (small-size explosion) of one of the fuse bolt. "It takes a lot of work to reach it," Vladimir Syromyatnikov, head of the department of electromechanics and large-size space structures of the Energia rocket and space corporation, explained, referring to the significant disassembly that must be done to reach the bolt, inspect the area for damage, and replace it. Such bolts generally are self-contained and do not inflict damage on surrounding structure.

The explosion of a fuse took place in the assembly and test facility in Baikonur during a repeated test of the power-supply system of the spaceship, which is part of preparations for the launching. Energia experts explained that “the fuse bolt is intended for the separation of the spaceship’s compartments during the return to the Earth.”

If the explosion was triggered when faulty ground equipment sent too large a surge into the circuit, the impact of the incident on other systems should be minimal. But if the accidental firing was the result of a flaw in the bolt, all other such bolts on the spacecraft may have to be verified.

And if bolts from the same batch are also installed on the Soyuz currently docked to the space station, a significant effort will be required to re-qualify them or to develop contingency plans if one or more of them misfire on the planned return to Earth, initially scheduled for 17 October.

Failures of such explosive bolts are rare but not unprecedented. In 1969, the failure of the separation system on the Soyuz 5 spacecraft led to it entering Earth's atmosphere with the crew-carrying command module still loosely attached to the equipment-carrying service module. Off balance, the spacecraft turned its unprotected side into the super-hot plasma and began burning, but the G-force stresses soon tore the two sections apart, and the capsule aligned right itself barely in time.

Delaying the launch would also delay the landing of the current station crew, and this would lead to mounting safety issues. The Soyuz spacecraft has a certified lifetime of about six and a half months in space, and beyond that point, high-energy chemicals in its propulsion system threaten to become unstable. Other mechanical systems gradually lose reliability as well, but these concerns would take weeks to become significant.

The Soyuz spaceship will take to ISS the tenth expedition – Salidzhan Sharipov from Russia and NASA astronaut Leroy Chiao. Lieutenant Colonel Yuri Shargin of the Russian Space Forces will go to ISS with them with a ten-day visiting mission.

The Soyuz-TMA spaceship that is to fly in October will be the one to be used by the ISS crew to return to the Earth in April 2005. Among the members of that crew there will be the ESA astronaut of the Italian nationality.